Synergistic mixtures of selected amino acids

ABSTRACT

Novel synergistic fungicidal compositions used for protecting seeds, plants and other vegetative material against fungi contain a mixture of one or more compounds selected from group A and one or more compounds selected from group B. Compounds from group A are selected from Beta-Amino butyric acid and its N-benzoyl-octyl ester derivatives. Compounds from group B are selected from the group of fosetyl aluminum, dimethomorph, a mixture of folpet and ofurace (45:5), folpet fencaramid (Bayer SZX), mancozeb, cymoxynil, methalaxyl, the single optical isomer of metalaxyl, a mixture of cymoxamil and mancozeb (4:1), copper sulfate, copper hydroxide, copper sulfate hydrate, azoxystrobin, and acidenzolar-s-methyl.

This application is a 371 of PCT/IL 98,00167, filed Apr. 8, 1998.

The present invention concerns synergistic fungicidal mixtures. Thepresent invention more particularly concerns synergistic mixture ofβ-aminobutyric acid (hereinafter. referred to as BABA) and itsN-benzoyl-octyl ester derivatives for the control of plant diseases.

BACKGROUND OF THE INVENTION

Fungicides are often combined in mixtures for 3 main reasons: 1 to widenthe spectrum of antifungal activity to control several diseasesoccurring simultaneously in a crop 2. to exploit synergistic interactionbetween fungicides, by which the overall activity is increased and theconcentration of the compounds reduced, and 3. to delay the selectionprocess of resistant fungal individuals to one component of the mixture(Gisi, Phytopathology 86 1273-1279,1996).

Avoidence of plant disease in agricultural production may beaccomplished not only by using fungicides or fungicidal mixtures butalso by using “plant activators”, molecules which enhance the naturalresistance (defense) of the plant. Such activators which have no directfungicidal effect on the pathogen (Ryals et al The Plant Cell 8:1809-1819,1996), induce systemic acquired resistance (SAR) in the plantseveral days after application (Ibid).

To date only few molecules were reported to induce SAR in crop plantsviz. salicylic acid (SA), 2,6-dichloroisonicotinic acid (INA) benzol(1,2,3) thiadiazole -7-carbothiouic acid S-methyl ester (BTH) (Ibid),and DL-3-amino butyric acid (BABA, Cohen et al Plant Physiology 104:56-59,1994).

However whereas SA, INA or BTH have to be applied to the crop ahead ofinfestation (Ryals, et al Ibid) BABA can be applied post-infectionaly(Cohen et al Ibid).

The idea behind the present invention is to combine two methods ofdisease control—the direct-kill method operating on the target pathogenand the indirect method of activating the natural defense approach ofthe crop plant. Such two methods are combined by using mixtures of afungicide or fungicides (direct-kill) with BABA or its N-benzoyl-octylester derivative(SAR).

We show here that such mixtures are synergistic in controlling plantdiseases.

OBJECTIVES OF THE INVENTION

It is the objective of the present invention to provide novel mixturesof fungicides of β-aminobutyric acids. It is an objective of the presentinvention to provide a synergistic mixture of BABA and/or itsN-benzoyl-, octyl ester derivative with various other fungicides.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided synergisticfungicidal compositions comprising one or more compounds selected fromGroup A and one or more compounds selected from Group B; wherein thecompounds of Group A are selected from the group consisting of DL-3aminobutyric acid and its N-Benzoyl octyl ester, and the compounds ofGroup B are selected from the group consisting of fosetyl aluminum,dimethomorph, a mixture of folpet and ofurace (45:5), folpet, fencaramid(Bayer SZX), mancozeb, cymoxanil, methalaxyl, the single optical isomerof metalaxyl, a mixture of cymoxamil and mancozeb (4:1), copper sulfate,copper hydroxide, copper sulfate hydrate, azoxystrobin, andacibenzolar-s-methyl.

The present invention also provides an improved method of controllingfungi, especially late blight and downy mildews, applying to the plant acomposition containing an effective amount of one of these mixtures. Thepresent invention further provides an improved method of controllingPhytophthora infertan in potato or tomatoe, Pseudoperonospora cubensisin cucumber or melon, Plasmopera viticola in grapes, and Peronosporatabacina in tabacco.

DETAILED DESCRIPTION OF THE INVENTION Methodology

Plants 1. Potato (cultivar Alpha) were grown from tubers in 1 liter potsin sandy soil in the greenhouse. At 5 weeks after planting when they hadseveral shoots in a pot, with 10-12 leaves per shoot, plants were takenfor assays.

2. Cucumber (cultivate Dlila ) plants were grown from seed in 0.251liter pots containing sandy soil in the greenhouse. At 3 weeks aftersowing, when they developed 2 leaves they were used.

3. Grapes (cultivate Superior) plants were grown from cuttings (first inperlite and then in sandy soil) in pots in the greenhouse. At 8 weeksafter planting leaves were detached for experiments.

Fungal Pathogens. Potatoes were inoculated with sporangic ofPhytophthora infestans (resistant to metalaxyl). Cucumbers wereinoculated with sporangia of Pseudoperonospora cubensis (resistance tometalaxyl). Grapes were inoculated with Plasmopara viticola Chemicals.

1. DLβ-amino-butanoic acid (BABA)

2. DL-4-benzoyl-3-amino butanoic acid octylester (039-81)

3. Cymoxanil (Curzate)

4. phosetyl-aluminium (Alliette)

5. Mancozeb

6. Folpet

7. Metalaxyl, metalaxyl-Gold

8. Copper sulphate, copper hydroxide

9. (Mancozeb+dimethomorph, prepacked 600 g+90 g a.i.per 1 kg)

10. (Mancozeb+metalaxyl, prepacked 560 g+75 g a.i. per 1 kg)

11. Folpet+ofurace, 450 g+60 g a.i. per 1 kg)

12. Bayer-SZX (Fencaramid)

13. Mancozeb+Cymoxanil (4:1)

14. Azoxystrobin

15. Acibenzolar-s-methyl

16. Dimethomorph

Except BABA which was dissolved in water, all other chemicals orprepacked mixtures produced a suspension or emulsion in water.

Spraying The chemicals were sprayed onto the upper leaf surfaces ofeither potatoes or cucumbers with the aid of a fine glass atomizer.Control plants were sprayed with water. Experiments with grapes werecarried out using 12 mm leaf discs floating on 1 ml of the testcompound(s) in 24—well titer plates, upperside down.

Inoculation

Potatoes and cucumbers were inoculated one day after spraying. Grapeleaf discs were inoculated soon after floating.

Inoculation of potato was done by spraying the upper leaf surfaces ofthe plants with a sporangial suspension containing 2000 sporangia/ml.Sporangia were harvested 0.5 h before inoculation from infected potatotuber slices. Cucumbers were sprayed with a sporangial suspensioncontaining 1500 sporangia/ml. Sporangia were harvested from infectedcucumber plants kept in humid growth chambers (at 15° C.). Leaf discs ofgrapes were inoculated with 2 sporangial droplets containing each 300sporangia. Sporangia were harvested from infected leaves kept in petridishes on wet filter paper at 15° C. Inoculated plants or titer plateswere placed in a dew chamber at 18° C. overnight and then transferred toa growth chamber at 20° C. (12 h light/day 100 pE.m⁻².S⁻¹) for symptomproduction (late blight in potato and downy mildew in cucumber), or forsporulation of P. viticola in grape leaf discs.

General Procedure for Tabacco

One month old tobacco plants (cv.xanthi nc.). were sprayed onto theirfoliage with the test compounds. Two days later they were inoculatedwith 10⁴ spores/ml of Perouospora latacin of either the S or the Rstrain. Inoculated plants were placed in 100% relative humidity overnight and then incubated at 20° C. with 12 h light/day. A week afterinnoculation plants were again placed at 100%-RH at 18° C. in the darkto induce fungal sporulation. Sporulation was quantitated by removing 2cm² leaf discs from each leaf and counting with the aid of ahaemocytometer. The extent of sporulation inhibition was calculatedrelative to that in control (untreated) inoculated plants. Ed_(go) wascomputed after linear regression and of was calculated according toWadely.

General Procedure for Grapes

Leaf discs (2-cm²) were removed from the top leaves of grape plants (cv.Superior) grown in the greenhouse. Discs were floated (lower surfaceuppermost on the test solutions over filter paper of 9 cm diameter).Petri dishes. Leaf discs were immediately innoculated with 2 (10 ml)droplets of sporangial suspension (10⁴/ml) of Plasmopara viticola perdisc. Dishes were inculoated at 20° C. with 12 h light/day for 10 daysuntil fungal sporulation was quantified.

Disease Assessment

At the time intervals post inoculation specified in the Examples,infected leaf area in potato and cucumber was assessed visually. Incontrol inoculated plants most or all of the foliage (80-100%) wasdevastated by the disease. Percentage control of the disease by achemical treatment was calculated as

% control=(1−x/y)×100

whereas x=proportion leaf area diseased in treated plants

and y=proportion leaf area diseased in control plants.

In grapes, proportion of leaf discs showing sporulation were similarlyused.

Calculation of Control Efficacy and Synergism

Each chemical and each mixture was applied to plants at various doses ofthe active ingredient. Dose—response curves were produced andtransferred to log—dose probit response curves as described by Kosmanand Cohen (Phytopatholagy 86: 1263-1272, 1996). ED₉₀ values (doserequired for achieving 90% control of the disease) taken from thelog-probit 7 curves were used to calculate the Cotoxicity Factor (CF)according to the Wadely procedure (Kosman and Cohen, Ibid; Gisiphytopatcology 86: 1273-1279,1966). “CF” is defined as the ratio betweenthe expected dose and the observed dose that provide the same level ofdisease control (Kosman and Cohen, Ibid). The observed dose of eachcomponent of a mixture is taken from the experiment and the expecteddose of all mixture made of that components is calculated by the Wadelyformula:${{ED}_{90}\quad {expected}} = \frac{a + b}{\frac{a}{{ED}_{90}\quad {{obs}.A}} + \frac{b}{{ED}_{90}\quad {{obs}.B}}}$

where a and b are the absolute amounts of the components A and B in amixture and ED₉₀. obs.A and Ed₉₀ obs.B are the Ed₉₀ values of A and Bobtained by the experiment. CF values of>2.0 are considered to representa strongly synergistic mixture (Gisi, Ibid).

According to a further feature of the invention, there is provided afungicidal composition which comprises a compound of the inventiontogether with carrier. The active compound can be employed as a widevariety of formulations, for example as an aqueous dispersion, adispersible powder, as seed dressing, granules or dust. As a dispersionthe composition comprises an active compound together with a dispersingagent dispersed in a liquid medium, preferably water. It can be in aform of a concentrated primary composition which requires dilution witha suitable quantity of water or other diluent before application. Suchprimary compositions are a convenient way of supplying the consumer andpreferred example is a dispersible powder. A dispersible, powdercomprises an active compound, a dispersing agent and solid carrier. Thelatter can be, for example, kaolin, talc, or diatomaceous earth and inaddition, the dispersible powder can contain a wetting agent.

Other formulations include seed dressing, granules or dusts, in all ofwhich the active compound is associated with a solid carrier and whichare intended for direct application. They can be made by methods wellknown in the art. Preferably all compositions comprising a solid carrierare made by mixing the active compound in particulate form with aparticulate carrier.

The concentration of the active compound in the composition of theinvention can vary widely. In the case of a primary composition it ispreferably from 15% to 95% by weight, more especially from 50% to 80% byweight. A composition intended for direct application to a croppreferably comprises from 0.001% to 10% more, especially from 0.005% to5% by weight of the active compound, although the aerial spraying of acrop is contemplated compositions having higher concentrations, forexample up to 30% by weight may be chosen in preference.

The fungicidal composition of the present invention may be applied as aready-mixed composition, as a tank mix, or applying the compounds ofeach group separately.

Following the methods outlined above numerous mixtures were prepared andtheir activity against a variety of diseases were studied. The resultsof 35 studies are listed in Tables 1-35.

While the invention will now be described in connection with certainpreferred embodiments in the following examples it will be understoodthat it is not intended to limit the invention to these particularembodiments. On the contrary, it is intended to cover all alternatives,modifications and equivalents as be included within the scope of theinvention, as defined by the appended claims. Thus, the followingexamples which include preferred embodiments, will serve to illustratethe practice of this invention, it being understood that the particularsshown are by way of example and for purposes of illustrative discussionof preferred embodiments of the present invention only and are presentedin the cause of providing what is believed to be the most useful andreadily understood description of procedures as well as of theprinciples and conceptual aspects of the invention.

TABLE 1 CONTROL OF LATE BLIGHT IN POTATO BY BABA COPPER SULFATE HYDRATEMIXTURE^(a) Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 2 8 32 125 250 1000 mg/L CF BABA — — —  0  0  0 13 2678 — Cu⁺² — 0 0 63 83 — — 143 — BABA + Cu⁺² 80 + 20 0 0 13 88 — — 126 4.770 + 30 0 0 50 93 — — 101 4.2 60 + 40 0 0 85 93 — —  85 3.9 ^(a)5 dayspost inoculation ^(b)Control plants showed 100% leaf blight

TABLE 2 CONTROL OF LATE BLIGHT IN POTATO BY BABA CYMOXANIL MIXTURE(CURZATE ^(R))^(a) Percent Disease Control^(b) mg/L Active IngredientED₉₀ Compounds Ratio 4 16 62 250 1000 mg/L CF BABA — 3 24 18 64 1498 —Cymoxanil — 36 73 64 98 128 — BABA + 80 + 20 9 9 3 79 — 294 1.6Cymoxanil 50 + 50 73 76 82 98 — 114 2.1 ^(a)5 days post inoculation^(b)Control plants showed 83% leaf blight

TABLE 3 CONTROL OF LATE BLIGHT IN POTATO BY BABA FOSETYL ALUMINUMMIXTURE^(a) Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 16 62 250 1000 mg/L CF Cultivar Cara^(b) BABA 9 9 9 243233 — Fosetyl − Al 9 24 24 70 1390 — BABA + 75 + 25 9 9 39 70 1311 1.9Fosetyl − Al 25 + 75 9 9 39 79 1142 1.4 Cultivar Draga^(c) BABA 0 0 0 531533 — Fosetyl − Al 33 33 50 93 856 — BABA + 75 + 25 67 67 93 93 639 1.7Fosetyl − Al 25 + 75 0 0 93 100 245 3.9 ^(a)5 days post inoculation^(b)Contact plants showed 83% leaf blight ^(c)Contact plants showed 38%leaf blight

TABLE 4 CONTROL OF LATE BLIGHT IN POTATO BY BABA MIXTURES OF MANCOZEB +DIMETHOMORPH MIXTURES^(a) Percent Disease Control^(b) mg/L ActiveIngredient ED₉₀ Compounds Ratio 4 16 62 250 1000 mg/L CF BABA — — 3 2418 64 1498 — MANCOZEB + — 70 73 82 98 — 115 — DIMETHOMORPH BABA + 80 +20 64 73 70 82 — 287 1.5 (MANCOZEB^(c) + 50 + 50 85 70 70 91 — 189 1.1DIMETHOMORPH) ^(a)5 day post innoculation ^(b)Control Plants showed 83%leaf blight ^(c)60% Mancozeb & 9% Dimethomorph

TABLE 5 CONTROL OF LATE BLIGHT IN POTATO BY BABA FOLPET/OFURACE (45 + 5)MIXTURE^(a) Percent Disease Control^(b) @ mg/L Active Ingredient ED₉₀Compounds Ratio 4 16 62 250 1000 mg/L CF BABA — 14 14 14 36 2617 FOLPET/77 89 99 100 — 19 OFURACE BABA + 50 + 50 74 81 99 100 — 22 1.8 (FOLPET/OFURCE) ^(a)7 days ^(b)Control plants showed 88% leaf blight

TABLE 6 CONTROL OF LATE BLIGHT IN POTATO BY BABA FOLPET - CYMOXANILMIXTURE^(a) Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 16 62 250 1000 mg/L CF BABA 22 22 22 69 1481 FOLPET 8195 98 100 84 CYMOXANIL 83 86 91 100 183 BABA + FOLPET + 60 + 25 + 15 7289 98 100 95 2.5 CYMOXANIL 25 + 60 + 15 92 86 95 100 104 1.3 ^(a)6 daypost innoculation ^(b)Control plants showed 80% leaf blight

TABLE 7 CONTROL OF LATE BLIGHT IN POTATO BY THE N - BENZOYL OCTYL ESTEROF BABA AND FENCARAMID^(a) Percent Disease Control mg/L ActiveIngredient^(b) ED₉₀ Compounds Ratio 2 8 32 125 250 1000 2000 mg/L CFBABA Derivative — — — 15 25 50 53 2395 Fencaramid  0 50 98 100 — — — 19BABA DERIVATIVE + 80 + 20 44 63 85 100 — — — 31 3.0 FENCARAMID 90 + 1013 50 56 94 — — — 97 1.8 ^(a)4 day post innoculation ^(b)Control plantsat 100% leaf blight

TABLE 8 CONTROL OF LATE BLIGHT IN POTATO BY N-BENZOYL OCTYL ESTER OFBABA, Cu (OH)₂ , (as 50% a.i), MANCOZEB^(a) Percent Disease Control bmg/L Active Ingredient ED₉₀ Compounds Ratio 4 16 62 250 1000 mg/L CFN-benzoyl octyl — 3 25 25 75 1261 ester derivative of BABA Cu(OH)₂ 0 013 75 — 298 Cu(OH)₂ + 70 + 30 0 3 44 50 — 416 Mancozeb N-benzoyl octyl80 + 20 3 3 25 75 300 2.6 ester derivative of BABA + Cu(OH)₂ N-benzoyloctyl 80 + 14 + 6 3 3 75 83 239 3.8 ester derivative of BABA + Cu(OH)₂ +mancozeb ^(a)7 days post innoculation ^(b)Control plants showed 100%leaf blight

TABLE 9 CONTROL OF LATE BLIGHT IN POTATO BY N-BENZOYL OCTYL ESTERDERIVATIVE OF FOLPET/OFURACE (45 + 5) AND THEIR MIXTURES^(a) PercentDisease Control @ mg/L Active Ingredient^(b) ED₉₀ Compounds Ratio 4 1662 250 1000 mg/L CF N-benzoyl octyl — 0 0 0 25 2011 ester derivative ofBABA Folpet + 0 0 3 73 — 301 Ofurace (9 + 1) N-benzoyl octyl 67 + 33 013 75 100 — 74 9.5 ester derivative 50 + 50 8 8 69 100 — 82 6.4 of 33 +67 3 19 75 98 — 15 3.6 BABA + (Folpet Ofurace ^(a)7 days postinnoculation ^(b)Control plants showed 100% leaf blight

TABLE 10 CONTROL OF LATE BLIGHT IN POTATO BY N-BENZOYL OCTYL ESTERDERIVATIVE OF BABA, AND MANCOZEB + CYMOXANIL; 4:1 AND THEIR MIXTURES^(a)Percent Disease Control^(b) mg/L Active Ingredient ED₉₀ Compounds Ratio4 16 62 250 1000 mg/L CF N-benzoyl — 0 0 0 25 2011 octyl ester — 0 25 2575 — 313 derivative of BABA Mancozeb + Cymoxanil N-benzoyl 67:33 25 6870 95 — 169 4.3 octyl ester 50:50 5 63 88 98 — 95 5.7 derivative 33:6725 69 90 100 — 52 8.3 of BABA + Mancozeb + Cymoxanil ^(a)7 days Postinnoculation ^(b)Control plant showed 100% leaf blight

TABLE 11 CONTROL OF LATE BLIGHT IN POTATO BY N-BENZOYL OCTYL ESTERDERIVATIVE OF BABA, FOLPET AND THEIR MIXTURES^(a) Percent DiseaseControl^(b) mg/L Active Ingredient ED₉₀ Compounds Ratio 4 16 62 250 5001000 2000 mg/L CF N-benzoyl octyl — — — 63 69 85 89 1514 esterderivative of BABA Folpet 70 75 90 95 — — —  141 N-benzoyl octyl 80 + 2050 80 85 93 — — —  167 3.1 ester derivative 67 + 33 13 76 86 96 — — — 130 2.8 of BABA + 33 + 67 63 76 78 88 — — —  224 0.9 Folpet 20 + 80 2575 73 97 — — —  140 1.2 ^(a)4 days post innoculation ^(b)Control plantsshowed 100% leaf blight

TABLE 12 CONTROL OF LATE BLIGHT IN POTATO BY N-BENZOYL OCTYL ESTERDERIVATIVE OF BABA, FENCARAMID (BAYER SZX) AND THEIR MIXTURES^(a)Percent Disease Control^(b) mg/L Active Ingredient ED₉₀ Compounds Ratio2 8 31 25 500 1000 2000 mg/L CF N-benzoyl octyl — — —  15 25 50 53 3204— ester derivative of BABA Fencaramid  0 50 98 100 — — —  19 — —N-benzoyl octyl 90:10 13 50 56  94 — — —  83 2.2 ester derivative 80:2044 63 85 100 — — —  31 3.0 of BABA + Fencarmid ^(a)5 days postinnoculation ^(b)Control plants showed 100% leaf blight

TABLE 13 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, COPPER SULPHATEHYDRATE (EXPRESSED AS mg/L Cu⁺⁺) AND THEIR MIXTURES^(a) Percent DiseaseControl^(b) mg/L Active Ingredient ED₉₀ Compounds Ratio 16 62 250 1000mg/L CF BABA 43 43 57 72 1468 Ratio 2 8 32 125 Cu⁺⁺ 57 72 80 89  105BABA + Cu⁺⁺ 80 + 20 72 72 86 89  102 4.0 70 + 30 57 72 72 89  111 2.760 + 40 57 72 86 89  102 1.9 ^(a)7 days post innoculation ^(b)Controlplants showed 88% leaf infection

TABLE 14 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, (EX- PRESSED ASCu(OH)₂) (Cu(OH)₂ + MANCOZEB) AND THEIR MIXTURES Percent DiseaseControl^(b) mg/L Active Ingredient ED₉₀ Compounds Ratio 4 16 62 250 1000mg/L CF BABA — 33 33 50 67 1576 Cu(OH)₂ 67 67 77 80 —  304 Cu(OH)₂ +70 + 30 67 67 83 93 —  174 mancozeb BABA + 80 + 20 67 70 77 90 —  2104.1 Cu(OH)₂ BABA + 80 + 14 + 6 70 70 90 90 —  191 3.2 Cu(OH)₂ + mancozeb^(a)4 days post innoculation ^(b)Control plants were 83% infected

TABLE 15 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, (FOLPET/OFURACE45 + 5) Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 4 16 62 250 1000 mg/L CF BABA —  0 29 57 71 1273 — Vamin43 57 71 91 —  206 — BABA + Vamin 67 + 33 14 21 57 97 —  166 2.8 50 + 5014 43 71 89  217 2.1 33 + 67 29 57 74 89  214 1.3 ^(a)7 days postinnoculation ^(b)Control plants were 88% infected

TABLE 16 CONTROL OF DOWNY MILDEW CUCUMBER BY BABA AND (MANCOZEB +CYMOXANIL; 4:1) Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 4 16 62 250 1000 mg/L CF BABA —  0  29  57  71 1273 —(Mancozeb + 14  80  97 100  33 — Cymoxanil) BABA + 67 + 33 21 57  77  97—  135 0.7 (Mancozeb + 50 + 57 74 100 100 —  20 3.2 Cymoxanil) :50 33 +29 94 100 100 —  14 3.5 :67 ^(a)7 days post innoculation ^(b)Controlplants were 88% infected

TABLE 17 CONTROL OF DOWNY MILDEW CUCUMBER BY BABA AND (MANCOZEB +METALAXYL) Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 4 16 62 250 1000 mg/L CF BABA —  0 15  3 59 1443 —Mancozeb + 34 53 71 82 —  268 — Metalaxyl BABA + 88 + 12  0  0  9 96 — 221 4.3 Mancozeb + 75 + 25 18 44 53 81 —  281 2.4 Metalaxyl 50 + 50 3876 76 96 —  150 3.0 ^(a)6 days post innoculation ^(b)Control plants were88% infected

TABLE 18 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, FOL- PET &METALAXYL^(a) (87:13) Percent Disease Control^(b) ED₉₀ mg/L ActiveIngredient mg/ Compounds Ratio 4 16 62 250 1000 LF CF BABA —  0 15  3 591443 — Folpet &  0  0 56 76 —  280 — Metalaxy (87 + 13) BABA + 88 + 1212  0 59 81 —  260 3.7 [Folpet + 75 + 25 68 53 56 71 —  393 1.8metalaxyl] 50 + 50  0 38 62 68 —  339 1.4 ^(a)6 days post innoculation^(b)Control plants were 88% infected

TABLE 19 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, FOL- PET &METALAXYL^(a), (7 + 1) (MANCOZEB + METALAXYL), (FOLPET + OFURACE) ANDTHEIR MIXTURES Percent Disease Control^(b) mg/L Active Ingredient ED₉₀Compounds Ratio 4 16 62 250 1000 mg/L CF BABA — 12 19 25 31 3218Folpet + metalaxyl 62 82 90 97 —  112 BABA + 80:20 62 70 80 85 —  2472.0 [Folpet + metalaxyl] 50:50 75 77 80 97 —  133 1.6 (Mancozeb + 77 8595 97 —  100 — metalaxyl) BABA (Mancozeb + 80 + 20 82 87 92 97 —  1054.2 metalaxyl 50 + 50 82 92 97 97 —  92 2.1 (Folpet + Ofurace) 37 50 6282 —  279 — BABA + (Folpet + 80:20 50 62 80 92 —  187 5.5 Ofurace) 50:5077 97 92 100  —  33 15.6 ^(a)7 days post innoculation ^(b)Control plantswere 100% infected

TABLE 20 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, METALAXYL SINGLEISOMER, MANCOZEB AND THEIR MIXTURES^(a) Percent Disease Control^(b) mg/LActive Ingredient ED₉₀ Compounds Ratio 4 16 62 250 1000 mg/L CF BABA — 8  8  8 38 2155 mancozeb  0  8 23 72 —  315 Metalaxyl Single  0  0  0 8 —  844 Isomer BABA + 55 + 40 + 5  23 23 54 75 —  313 2.0 mancozeb +50 + 40 + 10 38 25 31 80  314 2.0 Metalaxyl Single 40 + 40 + 20  8 15  831  689 0.9 Isomer 45 + 50 + 5   8  8 54 72  309 1.7 40 + 50 + 10  8 3154 89  228 2.3 30 + 50 + 10  8 15 31 83  273 1.9 35 + 60 + 5  54 54 7886  239 2.0 30 + 60 + 10 46 38 54 85  268 1.7 20 + 60 + 20 61 69 69 83 281 1.6 25 + 70 + 5  38 46 78 97  139 3.0 20 + 70 + 10 38 23 63 94  1942.1 10 + 70 + 20 38 69 23 78  362 1.1 ^(a)6 days post innoculation^(b)Control plants were 81% infected

TABLE 21 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, ALIETTE, CYMOXANILAND THEIR MIXTURES Percent Disease Control^(a) mg/L Active IngredientED₉₀ Compounds Ratio 16 62 250 1000 mg/L CF BABA 37 67 76 85 975 —Aliette 45 85 98 99 245 — Cymoxanil 0 20 58 72 1229 — BABA + Aliette +Cymoxanil 60 + 25 + 15 63 70 88 95 584 1.0 25 + 60 + 15 70 85 98 100 1003.4 ^(a)Control plants were 100% infected

TABLE 22 CONTROL OF DOWNEY MILDEW IN CUCUMBER BY BABA, MANCOZEB,CYMOXANIL AND THEIR MIXTURES Percent Disease Control^(a) mg/L ActiveIngredient ED₉₀ Compounds Ratio 4 16 62 250 1000 mg/L CF BABA — 0 13 5063 1413 — Mancozeb 75 87 90 92 — 167 — Cymoxanil 13 25 38 50 — 506 —BABA + Mancozeb + Cymoxanil 60 + 25 + 15 63 75 83 95 152 3.0 25 + 60 +15 75 87 90 95 136 1.8 ^(a)Control plants were 100% infected

TABLE 23 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, BAYER SZX(FENCARAMID) AND THEIR MIXTURES Percent Disease Control^(b) @ mg/LActive Ingredient ED₉₀ Compounds Ratio 2 8 31 125 500 1000 2000 mg/L CFBABA 61 72 74 2354 FENCARAMID 78 83 95 100 19 BABA + FENCARAMID 80 + 2038 58 83 100 33 2.8 50 + 50 60 80 98 100 14 2.7 20 + 80 78 85 98 100 131.8 ^(a)5 days post innoculation ^(b)Control plants were 81% infected

TABLE 24 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, BAYER DIMETHOMORPH(DMN) AND THEIR MIXTURES Percent Disease Control^(b) Compounds Ratio @mg/L Active Ingredient BABA 1000 gave 17% Control DMN 5 ppm gave 32%Control BABA + DMN gave 74% Control 1000 + 5 ppm $\begin{matrix}{{{Synergy}\quad {ratio}} = \frac{74 = 74}{\frac{17 = {32 - {\left( {17\quad 32} \right)\quad 33}}}{100}}} \\{= 2.24}\end{matrix}$

TABLE 25 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, FOLPET, CYMOXANILAND THEIR MIXTURES^(a) Percent Disease Control^(b) @ mg/L ActiveIngredient ED₉₀ Compounds Ratio 16 62 250 1000 mg/L CF BABA 6 22 48 82107 2 FOLPET 43 84 95 97 403 48 63 82 97 524 BABA + FOLPET + CYMOXANIL25 + 60 + 15 76 87 95 99 247 2.0 ^(a)5 days post inoculation ^(b)Controlplants were 95% infected

TABLE 26 CONTROL OF DOWNY MILDEW IN CUCUMBER BY BABA, PHOSETYL-ALUMINIUMAND THELR MIXTURES^(a) Percent Disease Control^(b) mg/L ActiveIngredient ED₉₀ Compounds Ratio 16 62 250 1000 mg/L CF BABA 10 43 43 711386 — Phosetyl-Aluminium 71 71 94 86 638 — BABA + Phosetyl-Aluminium12 + 88 43 43 86 100 261 4.7 25 + 75 0 14 71 97 551 1.9 50 + 50 0 14 5783 1009 0.9 75 + 25 — 57 57 86 918 0.8 88 + 12 14 29 71 86 931 0.7 ^(a)7days post innoculation ^(b)control plants were 88% infected

TABLE 27 CONTROL OF LATE BLIGHT IN POTATO BY BABA, BION AND THEIRMIXTURES^(a) Percent Disease Control Ratio mg/L Active Ingredient ED₉₀Compounds (w/w) 250 500 1000 mg/L CF BABA 38 75 93 776 — BION 13 25 781173 — BABA + 38 78 98 639 1.3 ACIBENZOLAR- S-METHYL (10 + 1)

TABLE 28 CONTROL OF LATE BLIGHT IN TOBACCO BY BABA, AZOXYSTROBINEMIXTURE AND THEIR MIXTURES, FUNGAL ISOLATE = R Percent Disease ControlRatio mg/L Active Ingredient ED₉₀ Compounds (w/w) 5 10 25 50 100 200mg/L CF BABA — — — 0 13 100 171 AZOXYSTROBINE 13 81 81 81 93 — — 27BABA + AZOXYSTROBINE  5 + 1 25 100 100 100 41 2.2 10 + 1 38 81 100 10054 2.1 15 + 1 50 81 100 100 53 2.4

TABLE 29 CONTROL OF DOWNY MILDEW IN TOBACCO BY BABA,ACIBENZOLAR-S-METHYL, RIDOMTL-GOLD AND THELR MIXTURES: Fungal isolate =R Percent Disease Control Ratio mg/L Active Ingredient ED₉₀ Compounds(w/w) 16 62 250 mg/L CF BABA — 3 27 51 406 BION — 76 76 99 88RIDOMILGOLD — 49 37 58 416 BABA + 75 + 1 48 78 99 90 3.1ACIBENZOLAR-S-METHYL 10 + 1 45 93 100 52 5.9 15 + 1 22 84 91 186 1.820 + 1 14 74 98 116 3.5 BABA + RIDOMIL GOLD 7.5 + 1 27 63 97 150 2.710 + 1 34 44 99 145 2.8 15 + 1 23 52 78 282 1.4 20 + 1 0 20 91 239 1.4BABA + 7.5 + 1 + 1 37 63 95 174 1.7 ACIBENZOLAR-S-METHYL + RIDOMIL-GOLD10 + 1 + 1 45 71 92 190 1.7 15 + 1 + 1 37 84 82 230 1.5 20 + 1 + 1 57 9898 84 4.2

TABLE 30 CONTROL OF DOWNY MILDEW IN TOBACCO BY BABA,ACIBENZOLAR-S-METHYL, CURZATE RIDOMIL-GOLD AND THEIR MIXTURES: Fungalisolate = R Percent Disease Control Ratio mg/L Active Ingredient ED₉₀Compounds (w/w) 100 200 400 mg/L CF BABA — 37 62 100 270 —ACIBENZOLAR-S-METHYL — 37 50 80 443 — CURZATE — 25 25 62 596 —RIDOMILGOLD 20 35 42 >1000 — BABA + 10 + 1 62 100 100 113 2.3ACIBENZOLAR-S-METHYL 15 + 1 50 100 100 118 2.3 BABA + CURZATE 10 + 1 62100 100 113 2.5  5 + 1 37 62 100 270 1.1

TABLE 31 CONTROL OF DOWNY MILDEW IN TOBACCO BY BABA,ACIBENZOLAR-S-METHYL, RIDOMIL-GOLD AND THEIR MIXTURES: Fungal isolate =S Percent Disease Control Ratio mg/L Active Ingredient ED₉₀ Compounds(w/w) 0.5 5 50 mg/L CF BABA — 0 27 59 78 — ACIBENZOLAR-S-METHYL — 54 7685 52 — RIDOMILGOLD 100 100 100 0.2 — BABA + ACIBENZOLAR-S- 7.5 + 1  8585 99 15 4.9 METHYL 10 + 1 86 94 100 4 18.7 15 + 1 75 84 100 5 15.1BABA + RIDOMIL-GOLD 7.5 + 1  94 100 100 0.5 3.3 10 + 1 99 100 100 0.45.4 15 + 1 88 90 100 4.3 2.1 BABA + ACIBENZOLAR-S- 7.5 + 1 + 1  99 100100 0.4 4.4 METHYL + RIDOMIL- GOLD 10 + 1 + 1 100 100 100 0.2 12.2 15 +1 + 1 73 100 100 0.6 5.3

TABLE 32 CONTROL OF DOWNY MILDEW IN GRAPES BY BABA, ACIBENZOLAR-S-METHYLAND THEIR MIXTURES IN LEAF DISCS Percent Disease Control Ratio mg/LActive Ingredient ED₉₀ Compounds (w/w) 0.31 1.25 5 20 50 100 mg/L CFBABA — —  15  93 95 99 38   — ACIBENZOLA 0 27 75 100 — —  6 — R-S-METHYLBABA + 10 + 1  0 37  68 100 — — 6.6  3.9 ACIBENZOLA R-S-METHYL 15 + 1 6082 100 100 — — 1.4 19.8

TABLE 33 CONTROL OF DOWNY MILDEW IN GRAPES BY BABA, ALLIETTE AND THEIRMIXTURES IN LEAF DISCS Percent Disease Control Ratio mg/L ActiveIngredient ED₉₀ Compounds (w/w) 1.25 2.5 5 10 20 50 mg/L CF BABA — 38 4481 86 92 33 — ALLIETTE 13 36 38 40 48 81 — 24 BABA + ALLIETTE 1 + 1 4481 87 89 92 — 12 2.3 3 + 1 44 69 88 92 95 — 10 3.0 5 + 1 25 31 43 47 83— 22 1.4 7 + 1 24 31 34 56 62 — 30 1.0 9 + 1 22 34 39 55 61 — 31 1.0

TABLE 34 CONTROL OF DOWNY MILDEW IN GRAPES BY BABA, CURZATE AND THEIRMIXTURES, IN LEAF DISCS Percent Disease Control Ratio mg/L ActiveIngredient ED₉₀ Compounds (w/w) 1.25 2.5 5 10 20 50 mg/L CF BABA — — 2536 78 83 91 36 — CURZATE 11 39 58 66 55 — 27 — BABA + CURZATE 1 + 1 5161 68 81 89 — 16 1.9 3 + 1 62 70 77 86 93 — 13 2.6 5 + 1 69 74 81 89 95— 11 3.1 7 + 1 49 68 74 78 89 — 16 2.2 9 + 1 21 39 58 73 82 — 17 2.1

TABLE 35 CONTROL OF DOWNY MILDEW IN GRAPES BY BABA, DIMETHOMORPH ANDTHEIR MIXTURES, IN LEAF DISCS Percent Disease Control Ratio mg/L ActiveIngredient ED₉₀ Compounds (w/w) 0.31 1.25 5 20 50 mg/L CF BABA — —  0 1060 90 44 — DIMETHOMORPH 40 30 60 90 — 19 — BABA + 1 + 1 10 30 80 100   64.4 DIMETHOMORPH 3 + 1 30 60 60 60 28 1.2 5 + 1  0  0 20 60 30 1.2 7 + 1 0  0 10 50 34 1.1 9 + 1  0 40 50 40 40 1.0

What is claimed is:
 1. Synergistic fungicidal composition comprisingsynergistically effective respective amounts of D,L-3-aminobutyric acidand Mancozeb.
 2. A composition in accordance with claim 1 wherein theD,L-3-aminobutyric acid and Mancozeb are present in a weight ratio of9:1 to 1:9.
 3. The composition of claim 2 wherein said weight ratio is4:1 to 1:4.
 4. A method of administering a fungicidal composition inaccordance with claim 1 to a plant infested with fungus, wherein thefungus is selected from the group consisting of Phytophthora infestans,Pseudoperonspora Cubensis, Plasmopara veticola, and Peronosporatabacina.
 5. A method in accordance with claim 4 wherein the fungus isselected from the group consisting of Phytophthora infestans in potatoesand tomatoes, Pseudoperonspora Cubensis in cucumber and melons,Plasmopara veticola in grapes, and Peronospora tabacina in tobacco.
 6. Amethod of controlling fungal infections in plants comprising applying tothe plants or parts thereof a synergistic fungicidal compositioncomprising synergistically effective respective amounts ofD,L-3-aminobutyric acid and Mancozeb.
 7. A method in accordance withclaim 6 which comprises applying D,L-3-aminobutyric acid and Mancozeb ina weight ratio of 9:1 to 1:9.
 8. A method in accordance with claim 6wherein the plants are selected from the group consisting of potatoes,tomatoes, cucumbers, melons, grape vines, and tobacco.
 9. A method inaccordance with claim 6 wherein the fungus is selected from the groupconsisting of Phytophthora infestans, Pseudoperonspora Cubensis,Plasmopara veticola, and Peronospora tabacina.
 10. A method inaccordance with claim 9 wherein the fungus is selected form the groupconsisting of Phytophthora infestans in potatoes and tomatoes,Pseudoperonspora Cubensis in cucumber and melons, Plasmopara veticola ingrapes, and Peronospora tabacina in tobacco.
 11. The method of claim 7wherein said ratio is 4:1 to 1:4.